The proposed work on androgen metabolism will be conducted in the following broad areas: 1. Our studies on androgen and estrogen metabolism in man indicate the multiple factors in addition to the negative feedback can influence the secretion of LH from the pituitary. We will continue to investigate the effects of both androgens and estrogens on gonadotropin secretion and will particularly focus our attention on patients with amenorrhea. A classification of amenorrhea based on the responsiveness of gonadotropin secretion to estrogen and androgen administration will be established. 2. In order to understand the mechanism of androgen actions, the androgen receptor in mouse kidney will be further characterized by isoelectric focusing, DNA cellulose binding and column chromatography. Two forms of the androgen receptor will be sought: an inactive form which binds to progestins and an active form which binds to testosterone. The androgen receptor activity will be measured in patients with testicular feminization.